In reference to your question as to whether or not this is a dead ball:
8.02 The pitcher shall not-
(a)(1)Bring his pitching hand in contact with his mouth or lips while in the 18 foot circle surrounding the pitching rubber. EXCEPTION: Provided it is agreed to by both managers, the umpire prior to the start of a game played in cold weather, may permit the pitcher to blow on his hand.
Official Notes - Case Book - Comments: PENALTY: For violation of this part of this rule the umpires shall immediately call a ball. However, if the pitch is made and a batter reaches first base on a hit, an error, a hit batsman or otherwise, and no other runner is put out before advancing at least one base, the play shall proceed without reference to the violation. Repeated offenders shall be subject to a fine by the league president.
As you can see, neither the rule nor the OBR casebook give direction to the kill the ball. However, according to the JEA:
Customs and Usage: (1) Generally, when this violation is called, the umpire is able to signal the infraction and call “time” before the pitch is thrown. if the pitch is delivered, however, it is nullified unless the batter and all runners advance at least one base.